1. Field of the Invention
The present invention relates to a control device and a control method for a vehicle. More particularly, the present invention relates to control of a vehicle in which automatic stop and automatic start of an engine are carried out during traveling of the vehicle.
2. Description of Related Art
A so-called idle stop vehicle has been known in which an engine is automatically stopped on the basis of a predetermined automatic stop condition and the engine is automatically started on the basis of a predetermined automatic start condition during a stop of the vehicle. For example, a vehicle disclosed in Japanese Patent Application Publication No. 2011-219026 (JP 2011-219026 A) is one such example. In JP 2011-219026 A, an engine is automatically stopped on the basis that a vehicle speed is zero, that a battery and an engine water temperature are in predetermined states, that a brake pedal is depressed, or the like. In addition, it is described that the automatic start conditions include a temperature of an evaporator constituting an air conditioning system as one of the conditions and that, when the temperature of the evaporator becomes higher than a predetermined temperature, the engine is automatically started.
It has been suggested to execute the automatic stop and the automatic start of the engine not only during the stop of the vehicle but also during the traveling of the vehicle. In addition, economical control has been known in which a target temperature of the evaporator is temporarily increased for a purpose of improved fuel efficiency. When the economical control is executed in such a vehicle, the temperature of the evaporator is increased. If the engine is automatically stopped at this time, the evaporator reaches the predetermined temperature at which the engine is restarted in a short period. Accordingly, a period to stop the engine is reduced, and thus the fuel efficiency is possibly worsened.